Adnan Shahpurwala

At this workshop I attended in India, we first made a line follower robot with one L293D driver circuit, two infrared sensors and two motors. Next we made an obstacle avoidance robot just by putting the sensors in an upright position. Both the pictures are of the line following robot. Later we learnt C programming and using a PIC micro controller with MPLABS software and also how to wirelessly control a robot using XBEE transmitter and receiver. After that we wrote a few codes for other types of bots and then we moved on to controlling a robot with a 3 axis accelerometer and a PIC micro controller.

The game showed is about lights getting lit from right to left and back and one has to click a push button when the centre light is lit. Every time one does that, the score increments by 1 on the small LCD screen and the speed at which the LED’s get lit gets faster which makes the game difficult as time passes. I made this game to serve as an attraction for IEEE registration day, an annual event where we spread awareness about IEEE and get students to register for the international membership.

It was one of those nights, during my internship at IIT Kharagpur, where I got extremely bored and the voice inside my head was telling me to make something fun. Next moment, I headed out on my cycle, went to the electronics store, got the parts and made this simple game. Got this idea after seeing what other hobbyists make when they get bored. Basically, when the laser falls on the LDR, its resistance changes which is senses by the Arduino. The Arduino then tells the servo motor to work and make the target go down. Although this is a simple idea, it taught me how to use servo motors with an Arduino. The video is hilarious so do check it out :)

This circuit makes use of the monostable mode. The LDR's (light dependant resistor) resistance changes based on the incident light which sends a voltage signal senses by the 555 IC. I've also attached a switch (beside the LDR) to allow the user to choose if they want the night lamp to work when it gets dark or not. The circuit schematic is not mine and was borrowed from the internet.

Freshmen 1 semester would often bog me down with boredom. In order to overcome this, I decided to do something out of the box. Hence, I picked up an ebook on Arduino microcontroller and started making an electronic dice. It seemed like a redundant thing to make, but was at least better than wiling my time away. Every time the Arduino was given an input to switch on, it would read the random static charge in the surrounding environment (via an analog pin), convert that to a random seed number, and generate a random number between 1-6 for the dice. The code was initially written for lighting the “nth” LED to indicate the output number “n”. To increase ease of recognising the output, I modified the code by making “n” number of LED’s light up when ‘n’ was the output.

I wanted to make music a more tantalising experience, hence I decided to integrate light with it. After searching a lot on the internet, I found a schematic which would help me adjust the brightness of LED lights according to the power output of the music. So, I purchased a TIP 31 transistor and wired it according to the schematic with two LED’s, a 3V button cell and a 3.5mm audio jack. Initially, I only made a prototype (shown above) to test the schematic. Once that checked out, I made the project bigger by lighting up my entire dorm room using a dc adapter, roll of LED lights, and a breadboard to make the circuit on. My room has never been boring ever since.

After watching a few YouTube videos, this was a very exciting project for an electronic craftsman like me. The way this circuit works is the NPN transistor creates a high frequency signal which goes through the primary coil (red color) containing 3 turns. This signal gets amplified by the secondary coil which has 275 turns and because of mutual induction, the secondary coil generates a high voltage high frequency wave. When the bulb is brought closer, the fluorescent coating inside the bulb gets energized which is why the bulb glows. It is interesting to note that only half of the bulb lights up.

Being a frequent traveller, I needed something portable to charge my cell phone. Hence I looked up a schematic online and made a portable USB charger using a 5V regulator, female USB port, and a 9V battery for the power source. Since I had a lot of food containers, I used that as my casing, making best out of waste. I also reused the USB cable of my old mouse and connected it to a Nokia charging pin. To test, I once again used an old cell phone and it worked. However, just like the solar panel, the phone took significant time to charge as the current output of the battery cannot match that of the normal chargers. Nevertheless, it is a very compact and handy piece of technology to have during emergencies.

“Go Green” is the new mantra on everybody’s mind and this led me to purchase a 6V, 8W solar panel from the local store. I then looked up the schematic for a basic 5V regulator circuit. It was made using a generic 5V regulator chip to clip off the input at 5 V and two capacitors to smooth the output as cell phones require stable input voltages. To test it, I first connected a multimeter at the output to check if it was producing the required voltage. After that, I connected a spare phone to the output and it worked like a charm! However, there was a small problem. My cell phone took a long time to charge as the current output of the solar panel was low (as power is low but voltage is constant). Nevertheless, it was a small step towards practically applying green technology using basic engineering skills.

Wanting to do something different with my old camera, with a little help from the internet I found a way to make it an infrared camera. I had to remove a small film from the heart of the camera which filters the infrared radiation. Now to block the visible spectrum of light I had to attach a piece of an old photo film used previously in photography. It works pretty good, the photo on the top right corner is a picture of an oven from my camera, the photo on the bottom left is of a bulb and the one beside it is me with an infrared LED pointing towards my forehead. With the help of my camera and an infrared LED, I can now sneak out in the dark without switching on any lights. This project helped me understand the light spectrum in a practical way.

Mumbai (in India) heat is a killer and in this oven, AC is not a luxury, but a necessity. Recently in July 2017 I visited my friend in Mumbai and seeing her sweat after working hard the entire day got to me. Her landlord doesn't provide her with an AC. I looked at it as a simple problem with a simple solution and made this handy air cooler by watching a video on YouTube (https://www.youtube.com/watch?v=4iTrI-itEpc&t=91s). She couldn't believe her eyes when she saw how well it worked! This brings me to an important topic - Engineering is only useful when it proliferates the betterment of society. Being an engineer, it is important to constantly think about solutions and act upon them when they are within ones reach. After all, knowledge is of no use when not used.

Along with learning, teaching and passing on knowledge has been of great interest to me. In Spring 2016, I took the lead on organizing a workshop where attendees would learn how to make two circuits -

1. A 555 timer based circuit which would make an LED blink.
2. A TIP31C based circuit which would make an LED's brightness vary with the beats of music.

This was the first workshop in the Engineering Department at AUS (American University of Sharjah) where students took back something tangible (the circuit) as well as intangible (knowledge). I also prepared a manual which attendee's could refer back to later on. From organizing, marketing, and executing the workshop, this experience was self-fulfilling.

At family gatherings, I would always see kids hovering around a computer and wiling away their time on YouTube/online games. This sight would often make me sad. No matter how much I spoke to them about doing other things which are creative/innovative, they would never do it. Later I realized its not their fault as they do not have any new avenue to try out things. This is where I came up with the idea of conducting a few workshops on electronics on the weekend. Along with learning a new skill, they enjoyed a lot and I got to spend some quality time with my cousins!

Buying new earphones every six months seemed a waste of money to me. I noticed that majority of the times earphones get spoilt because of wear and tear of the cable near the 3.5mm audio jack. Basically, because of an electric open circuit, the signal doesn’t get transmitted and hence no sound is produced on the other end. So, with a little bit of ripping off old earphones and help from the internet, I learnt how to repair earphones by replacing the audio jack. A friend of mine spoilt her original Beats earphones and was going to throw it. Instead I took them from her. I just replaced the starting part of the audio cable from an old AUX cable and voila! I saved a lot of money by repairing an original pair of Beats earphones (cost 99$) for less than 50 cents. The only drawback is the amplitude of volume got reduced a little bit because of the solder joint giving extra resistance, but I think I can live with that… considering I got original Beats earphones for peanuts.